1,720,994 research outputs found
Heavy metals in edible seaweeds and its potential health risk / Fadilah Mohammad Aris
Full text linkIntroduction: Heavy metals exist in many forms in the environment we live. As rapid pace of industrialization as well as indiscriminate human activities occurred, the geochemical cycles and biochemical balance of heavy metals in the nature has been drastically altered. Human bodies are exposed to heavy metals through the breathed air, water and food consumed (Singh et al., 2011 ). The traditional use of seaweeds as food in China, Japan and Korea has moved along when people from these countries migrated around the world. Seaweeds is consumed by small pockets of the population along the coastal areas of Peninsular Malaysia and East Malaysia (Ismail and Hong, 2002). Objectives: To determine heavy metals concentration in edible seaweeds and its potential health risk on human. Methodology: Cross sectional study was implemented whereby sixty samples of edible seaweeds imported from China and Korea were taken from several markets in Selangor. The samples were treated with wet acid digestion and subjected to Atomic Absorption Spectrometry for analysis of arsenic, cadmium and lead. Hazard Index (HI) was also determined. Results: The average concentration of cadmium and lead contravene the Malaysian Food Act 1983 Standard for cadmium of 1 mg/kg and 2 mg/kg for lead. There are significant difference between the concentration of arsenic, cadmium and lead in laminaria seaweed from China and Korea. HI for cadmium exposure is more than 1. Conclusion: HI indicates that people whom exposed to seaweeds with 0.00131 mg/kg/day of cadmium may develop potential adverse health effect. Industrialization in China leads to higher heavy metals concentration. Recommendation: The importation of seaweeds should be made with more precautious especially seaweeds from China
Sustainable and optimum generation mix possibilities for Malaysia power sector / Ahmad Amiruddin Mohammad Aris
Full text linkMalaysia generation mix has been long time dependence on a single fuel. This over-dependency is not a good option for long-term energy sustainability and security. This has led Malaysia to find other alternative resources to generate electricity. Some possible options are firstly using coal, however this leads to the dependency on imported coal and increase CO2 emission. Secondly by using Nuclear power plant, however the recent Fukushima incident and the public acceptance are the major consideration. Lastly using renewable energy (RE), however the resources are interruptible and expensive. This report proposes a study to determine optimal long-term generation mix for Malaysia using DP-based model at least cost
MEMS Resonator Q-factor microcontroller based measurement system / Ahmad Afdhaluddin Mohammad Aris
Full text linkThis paper presents the hardware and algorithm of Q-factor for MEMS Resonator using microcontroller-based measurement system. Conventionally, the characterization of Micro-Electro-Mechanical System (MEMS) resonator required bigger equipment such as oscilloscopes and function generators for analysis. The purpose of this project is to design a simplified system to characterize MEMS Resonator with improve portability. The design and development of signal generator and display system will be based on microcontrollers. Instead of manual data collection and characterization of the signal, the system shall be able to calculate the resonance frequency and calculate the quality factor of the MEMS Resonator. The design of signal generator will be based on sin(x) algorithm to produce digital library to the output. The microcontroller is able to log data time/cycle when signal sampling crosses zero line. The frequency and amplitude can be measured based on the time record and the biggest value of sampling data. Validating against measured value using conventional laboratory equipment, the natural frequency and quality factor obtained has 0.67% and 20% error
Automated calibration of baseline model for energy conservation using multi-objective Evolutionary Programming (EP) / Ahmad Amiruddin Mohammad Aris
Full text linkThis thesis presents multi-objective optimization approach in developing baseline energy using multi-objective Evolutionary Programming (EP). The co-simulation approach is proposed to obtain optimal solution of the thermal comfort-baseline energy configuration due to complexity in finding the trade-off between variables in reducing discrepancies between simulated energy consumption and measured data, furthermore leveraging automated computational calibration process. The proposed co-simulation process is developed by coupling building energy simulation (BES) software, Energy Plus with multi-objective evolutionary programming (MOEP) algorithm which is implemented in Matlab using coupling software, BCVTB. The proposed optimization approach is applied to a single storey Green Energy Research Centre (GERC) office building located in UiTM Shah Alam with multiple characteristics of fully conditioned and partially conditioned buildings. The office consists of five different size rooms with different purposes. In this regard, three building parameters are taken as decision variables including occupancies, lightings and electrical equipment. Meanwhile, output from Energy Plus i.e. hourly energy consumption and Predicted Percentage of Dissatisfied (PPD) are investigated as single and multi-objective optimization. The MOEP objective function is set to minimize the difference between simulated and measured energy consumption considering human thermal comfort in the building by using sum-weighted decision technique. To evaluate the accuracy of building energy model, hourly criteria for Normalized Mean Biased Error (NMBE) and Coefficient of Variance Root Mean Squared Error (CV(RMSE)) as proposed by the IPMVP are used. In the single objective approach, automated calibration method considering minimum baseline energy triumph over all other methods with NMBE and CV(RMSE) at 4.52 % and 10.8% respectively, hence meeting the acceptable range set by the IPMVP. The baseline energy is said calibrated and can be used for retrofit analysis. In multi objectives approach, MOEP with fixed weight SWA technique is the best alternative to solve multi-objectives problem for baseline calibration with NMBE and CV(RMSE) of 3.02% and 4.64% respectively. This study is also extended to investigate potential saving from two ECMs, 20w LED lighting and 5kW PV panel using the best variables configuration obtain from previous stage
Going Beyond Counting First Authors in Author Co-citation Analysis
Full text linkThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
Variations on the Author
Full text link“Variations on the Author” discusses two of Eduardo Coutinho’s recent films (Um Dia na Vida, from 2010, and Últimas Conversas, posthumously released in 2015) and their contribution to the general question of documentary authorship. The director’s filmography is characterized by a consistent yet self-effacing form of authorial self-inscription: Coutinho often features as an interviewer that rather than express opinions propels discourses; an interviewer that is good at listening. This mode of self-inscription characterizes him as an author who is not expressive but who is nonetheless markedly present on the screen. In Um Dia na Vida, however, Coutinho is completely absent form the image, while Últimas Conversas, on the contrary, includes a confessional prologue that moves the director from the margins to the center of his films. This article examines the ways in which these works stand out in the filmography of a director who offers new insights into the notion of cinematic authorship
Appropriate Similarity Measures for Author Cocitation Analysis
Full text linkWe provide a number of new insights into the methodological discussion about author cocitation analysis. We first argue that the use of the Pearson correlation for measuring the similarity between authors’ cocitation profiles is not very satisfactory. We then discuss what kind of similarity measures may be used as an alternative to the Pearson correlation. We consider three similarity measures in particular. One is the well-known cosine. The other two similarity measures have not been used before in the bibliometric literature. Finally, we show by means of an example that our findings have a high practical relevance.information science;Pearson correlation;cosine;similarity measure;author cocitation analysis
Dispelling the Myths Behind First-author Citation Counts
Full text linkWe conducted a full-scale evaluative citation analysis study of scholars in the XML research field to explore just how different from each other author rankings resulting from different citation counting methods actually are, and to demonstrate the capability of emerging data and tools on the Web in supporting more realistic citation counting methods. Our results contest some common arguments for the continued
use of first-author citation counts in the evaluation of scholars, such as high correlations between author rankings by first-author citation counts and other citation
counting methods, and high costs of using more realistic citation counting methods that are not well-supported by the ISI databases. It is argued that increasingly available digital full text research papers make it possible for citation analysis studies to go beyond what the ISI databases have directly supported and to employ more
sophisticated methods
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